When serializing CSS declarations we now support combining multiple
properties into a single shorthand property in some cases.
This comes with a healthy dose of FIXMEs, including work to be done
around supporting:
- Nested shorthands (e.g. background, border, etc)
- Shorthands which aren't represented by the ShorthandStyleValue type
- Subproperties pending substitution
This gains us a bunch of new test passes, both for WPT and in-tree
This exposed a few bugs which caused the following tests to behave
incorrectly:
- `tab-size-text-wrap.html`: This previously relied on a bug where we
incorrectly treated `white-space: pre` as allowing text wrapping. The
fix here is to implement the text-wrap CSS shorthand property.
- `execCommand-preserveWhitespace.html`: We don't correctly serialize
shorthand properties. This is covered by an existing FIXME in
`CSSStyleProperties::serialized()`
- `white-space-shorthand.html`: The last 5 subtests here fail as we
don't correctly handle shorthand properties in
`CSSStyleProperties::remove_property()`. This is covered by an
existing FIXME in said function.
Major browsers seem to preserve `white-space: pre/pre-wrap` styles in a
`<div>` when deleting the current selection through an editing command.
The idiomatic way to support this is to have a command with a "relevant
CSS property" to make sure the value is recorded and restored where
appropriate, however, no such command exists.
Create a custom command (internal to Ladybird) that implements this
behavior.